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Last full review/revision Jun 2021| Content last modified Jun 2021
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What is endometriosis?

Endometrium is the tissue that lines the inside of your uterus (womb). That tissue grows every month during your menstrual cycle because it's getting ready to support a baby. If you don't become pregnant, the endometrium comes off. It bleeds when it comes off. That bleeding is your menstrual period. After your period stops, the endometrium begins growing again.

Endometriosis is a condition caused by endometrial tissue growing outside of your uterus, usually in other areas inside your belly. Often the tissue grows on or around your ovaries, uterus, and fallopian tubes. Your fallopian tubes carry eggs from your ovaries to your uterus. You could have endometriosis in one spot or in many spots.

Any endometrial tissue that's in the wrong place acts just like endometrial tissue inside your uterus. That is, it grows and bleeds every month with your period. That bleeding can hurt. Sometimes the bleeding causes scar tissue to grow. The scar tissue sometimes blocks your fallopian tubes, which makes it hard to get pregnant.

  • Endometriosis can be painful, usually before and during your period and during sex

  • It can make it hard for you to get pregnant

  • Doctors diagnose endometriosis by looking through a thin viewing tube inserted near your belly button

  • Doctors can treat endometriosis with medicines or sometimes surgery

What causes endometriosis?

The exact cause of endometriosis isn't clear. With endometriosis, a few small pieces of the endometrial tissue that should leave your body with your period blood could instead travel up the fallopian tubes. One of those small pieces could even get inside your belly and start to grow.

Endometriosis sometimes runs in families.

What are the symptoms of endometriosis?

Pain is the most common symptom. Different women may have different types of pain:

  • Pain in your lower belly, especially before and during your period

  • Pain during sex

  • Pain when you pass stool (poop)

  • Pain when you urinate (pee)

During pregnancy, symptoms may stop for a while or sometimes forever. Symptoms often stop after menopause.

How can doctors tell if I have endometriosis?

Doctors may suspect endometriosis if:

  • You have belly pain that seems to come and go with your period or when you have sex

  • You have difficulty becoming pregnant

To see for sure whether you have endometriosis, the doctor may look inside your belly using a flexible viewing tube (laparoscopy). During this procedure, you will have anesthesia and then your doctor will insert the viewing scope through a small cut (incision) near your belly button.

Other tests, such as blood tests, ultrasound, CT scan, and x-rays, aren't very good for detecting endometriosis.

How do doctors treat endometriosis?

Treatment depends on your symptoms, pregnancy plans, age, and the stage of endometriosis.

Doctors treat endometriosis with:

  • Medicines called NSAIDs (nonsteroidal anti-inflammatory drugs) to help with pain

  • Medicines that contain hormones (such as birth control pills)

  • Surgery using a laparoscope to remove or destroy the misplaced endometrial tissue

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